Dr. Mehmet Oz, the celebrity TV doctor nominated by President Trump to oversee Medicare and Medicaid, has been a relentless promoter of controversial private insurance plans for older Americans.

“I’d be signing up,” he told viewers, directing them to a call center in an episode that is still available on his YouTube channel.

What Dr. Oz did not tell the audience was that he made money from touting the plans, known as Medicare Advantage. The for-profit company operating the call center, TZ Insurance Solutions, paid to be featured.

Dr. Oz even became a licensed broker for TZ Insurance in almost every state, according to regulatory filings newly unearthed by The New York Times, with the idea that he could sell plans directly to viewers.

He may be one of America’s best-known daytime TV personalities, or “America’s doctor,” as Oprah Winfrey called him. But little is known about exactly how he monetized his fame over the years. All told, his business and family ventures are valued in the neighborhood of roughly $90 million to $335 million.

An examination by The Times of his myriad financial interests revealed not only opaque ties with the industries he may soon regulate but also a coziness with health care companies that lawmakers have already highlighted in questioning his independence.